Three functional neuroimaging (H20-15 PET) studies were completed by VSS scientists this year. These included studies of speech and language in normal volunteers (twenty subjects); studies of central organization for speech, language and mechanisms of dysfluency in developmental stutterers (twenty patients); and a study of the functional neuroanatomy of speech vs. sign language (ASL) production (fourteen hearing children of deaf adults). The results are in the process of being analyzed, written up and submitted for publication. A study of presynaptic dopamine function (using fluorodopa) was completed in patients with Tourette syndrome (n=7) which is currently being analyzed. A functional neuroimaging (H20-15 PET) study of affected members of a cluttering family was initiated. Three pilot studies using echoplanar imaging (fMRI) techniques on the 4 Tesla system were conducted. The data were used to develop analytic techniques and initiate the design of acoustic and structural modifications of 4 T hardware necessary for speech studies. Protocols are in place for fMRI studies in individuals who stutter and have Tourette syndrome pending equipment delivery. GRANT=Z01DC00007 The Hearing Section operates an audiologic consultation service for the NIH intramural program. The staff collaborated on 14 protocols from 6 institutes. New this year are: Elective Mutism [NIMH]; clinical staging of the Autosomal Dominant Cerebellar Ataxias (ADCA) [NINDS]; Beckwidth Wiederman syndrome [NCI]; and Von Hippel-Lindau syndrome (VHL) [NCI and NINDS]. Data collection on patients in the Waardenburg study [NIDCD] was completed. Audiologic studies are being done on patients with muscular dystrophy with a possible relation to nonsyndromic hereditary hearing impairment. We have nearly completed patient data acquisition in a special subgroup of patients with VHL with an aggressive endolymphatic sac tumor (ELST). Our data will provide a detailed and systematic study of the auditory system changes in VHL patients with ELST. The ADCA study and the study of individuals with Gaucher's III disease who are undergoing enzyme replacement therapy [NINDS] are continuing. The CAU is collaborating with the NEI on defining the phenotype in the Usher syndromes. The CAU is providing audiologic patient care for participants from 58 additional protocols including type 2 neurofibromatosis [NCI]; audiologic findings in families with thyroid resistant hormone [NIDDK]; children and adults with AIDS [NCI and NIAID]; the long term study of normal healthy adults as well as adults with Down's syndrome and adults with Alzheimer's disease [NIA]; and patients with iron overload disorders. In addition, we provide audiologic baseline and serial follow-up studies for patients undergoing chemotherapy and other patients at risk for ototoxicities and support the ENT service the Inter-Institute Genetics Program.